But the proposal appears to be too extreme for some senior Russian officials. The foreign minister and the education minister spoke out flatly against an adoption ban, and the speaker of the upper house of parliament, a close ally of President Vladimir Putin, suggested the lower house members were letting emotions overtake rationality.

Putin himself, who has the authority to veto legislation, has made no public comment on the adoption provision. But his spokesman, Dmitry Peskov, indicated Wednesday the Russian leader regards it as excessive.

Peskov told the Interfax news agency that, although Putin understands the emotions that prompted the move, "the executive powers are taking a more restrained line."

Before becoming law, the measure has to pass a third reading in the State Duma, which is set for Friday, after which it would go to the upper house, the Federation Council, and then require Putin's signature.

The legislation further steps up animosity with Washington by calling for closure of political organizations in Russia that receive American funding.

Both strictures were included as amendments in the second reading in the State Duma of a bill prompted by last week's signing by President Barack Obama of a U.S. law that allows sanctions against Russians deemed to be human rights violators.

The U.S. law reopened a vein of deep resentment among many Russians over the United States' alleged meddling in Russian domestic affairs and Washington's perceived penchant for treating Moscow with condescension.

Putin has accused the U.S. of funding the wave of protests that rose against him over the past year and strongly criticized the new U.S. law.

Many Russians have long bristled at the adoption of Russian children by Americans, sensitive to the implication that Russians are hard-hearted or economically unable to take care of their own. The resentment is fanned by cases of abuse or deaths of Russian children adopted by Americans.

The anger hit the boiling point in 2010 when an American woman sent back a 7-year-old Russian boy she had adopted, saying he had behavioral problems and she didn't want him anymore.

In the wake of that scandal, and after long delay, Russia in July ratified an agreement with the U.S. on regulating adoptions. If the measure approved on Wednesday becomes law, Russia would abrogate that agreement.

Backers of the measure complain that the agreement is enforced poorly and that American courts are too lenient.

"Cases of the death of our children in the United States continue, and cases of not-guilty verdicts; we decided to take this tough decision to deprive Americans of the right to adopt Russian children," said Alexei Pushkov, chairman of the Duma's foreign relations committee.

The lawmakers "with impotent spite want to take revenge, but can't take revenge on Americans so try to recoup with children," Lyudmila Alexeyeva, one of Russia's most prominent human-rights activists, was quoted as saying by Interfax. "Instead of going to a country where they will try to be treated or at least be with families, they will stay to suffer here, in children's homes."

There are about 740,000 children without parental custody in Russia, according to UNICEF. Russians historically have been less inclined to adopt children than in many other cultures.

"Our deputies in the State Duma act absolutely like terrorists," said Oleg Orlov, head of the rights group Memorial. "They are fighting their external enemy — U.S. congressmen and senators, but .... take peaceful people as hostages: ourselves, the citizens of their own country, members of the civic movement, and children."

U.S. State Department spokeswoman Victoria Nuland declined to speculate on what the final Russian legislation would look like, but stressed that the American government is committed to upholding its agreements with Russia on adoptions.

The U.S. "continues to work closely with Russian authorities on inter-country adoption issues," Nuland said.

Civic organizations are likely to suffer in the provision on blocking U.S.-funded political organizations. A law passed this summer already requires non-governmental organizations that both receive funding from abroad and engage in political activity to register as "foreign agents;" as with the proposed new measure, a vague definition of what constitutes "political activity" could be used to crack down broadly.

The entire Russian retaliatory measure is being called the Dima Yakovlev bill, honoring a Russian-born toddler who died in the U.S. after his adoptive father left him in an automobile in the broiling heat for several hours. The father later was found not guilty of involuntary manslaughter.

The U.S. law, called the Magnitsky Act, stems from the case of Sergei Magnitsky, a Russian lawyer who was arrested after accusing officials of a $230 million tax fraud. He was repeatedly denied medical treatment and died in jail in 2009. Russian rights groups claimed he was severely beaten and accused the Kremlin of failing to prosecute those responsible.

The amended bill passed by the Duma on Wednesday also says any country that passes legislation similar to the Magnitsky Act also will be subject to an adoption ban.